
public class Contador {
	private int cont;

	public Contador(){
		cont = 0;
	}
	public int incrementa(int cont){
		this.cont += cont;
		if (this.cont < 0){
			this.cont = 0;
		}
		return this.cont;
	}
	public int decrementa(int cont){
		this.cont -= cont;
		if (this.cont < 0){
			this.cont = 0;
		}
		return this.cont;
	}
	public int getCont() {
		return cont;
	}
}
